Adolescence is a time of vulnerability for youth where depression rates increase, particularly in girls, and smoking behaviors are also initiated. Increased morbidity and mortality in women who are smokers has been highlighted by recent statistics showing that women now have an increased rate of smoking over the last several decades. Morbidity and mortality is usually defined by cardiovascular and respiratory disorders. Less attention has been paid to the effect of smoking on aspects of health such as the relationship between smoking and depression and anxiety, and in turn, their combined effects on reproductive and bone health. No studies have examined such issues in puberty. The aims of this study are to examine: (1) baseline relationships between puberty, smoking status, depression anxiety, reproductive and bone health, (2) causal direction between smoking status and depression and anxiety across 3 years, (3) characteristics of individual differences in developmental trajectories of: (a) reproductive and (b) bone health (accrual of bone mineral content; BMC) across a 3 year period, (4) the systematic effects of timing of puberty, smoking status and depression and anxiety on individual differences in developmental trajectories of reproductive and bone health (accrual of BMC) across a 3 year period, (5) the relationship of individual differences in developmental trajectories of adolescent reproductive health with individual differences in developmental trajectories of bone health across a 3 year period, and (6) whether baseline levels of smoking status, depression, and pubertal timing predict the simultaneous developmental trajectories of reproductive and bone health. The study will include 252 girls, ages 11-17 years enrolled in a cross-sequential design for three annual visits. Measures include smoking status, depression and anxiety, pubertal timing, gonadal and adrenal hormones, menstrual cycle information, and accrual of BMC. Examining the combined impact of smoking, depression and anxiety, on timing of puberty has import for future intervention and prevention strategies. Any negative influence during this critical period, such as smoking or depression, may have significant long-term consequences for bone (i.e. increased risk of osteoporotic fracture) or reproductive health (i.e. menstrual irregularity & endocrine disruption, infertility, dysmenorrhea). [unreadable] [unreadable]